ISTANBUL/ANKARA (Reuters) - Turkish authorities on Friday ordered the detention of 13 people for supporting the national medical association online, the Hurriyet newspaper reported, after the organization publicly opposed a military campaign in Syria.

A prosecutor this week ordered the detention of 11 senior members of the Turkish Medical Association (TTB), including its chairman, after the organization criticized the incursion into Syria’s Afrin, saying “No to war, peace immediately”. President Tayyip Erdogan accused the body of treason.

Three of the medical association members were later released on probation after appearing at an Ankara court on Friday, Hurriyet reported.

More than 300 people have been detained over social media posts that “criticized, opposed or misrepresented” the Afrin campaign, which started nearly two weeks ago, the government has said.

Among the 13 people targeted by the latest detention warrants was the gay rights activist Ali Erol, who had tweeted “War is a public health problem. #WeStandWithTTB”, his organization said. Another person was detained after tweeting “War is death, destruction, blood and tears. #NoToWar”, other local media reported.

Authorities also raided the residence of a lawyer who had publicly read the statement from the medical association, a lawmaker from the main opposition said.

“They don’t want to let anyone breathe,” Baris Yarkadas, of the Republican People’s Party (CHP), said on Twitter.

‘RULE OF LAW’

The crackdown on some of Turkey’s top doctors has drawn international criticism from the European union, rights group Amnesty International and the World Medical Association, which has called for their protection and an immediate end to the legal proceedings.

The doctors’ detentions were “worrying developments undermining the rule of law and independence and impartiality of the judiciary in Turkey”, EU Commissioner Johannes Hahn and EU foreign policy chief Federica Mogherini said in a statement.

The main business lobby warned that a crackdown on self-expression increased polarization and weakened the fight against terrorism.

“While battling terror, a Turkey that defends its freedoms and protects its variety of views will come out of this fight successfully,” TUSIAD said.

Erdogan’s critics see the latest arrests as emblematic of the purge that has followed a failed 2016 coup. More than 50,000 people have been arrested and 150,000 sacked or suspended from their jobs, moves the government says are necessary given the multiple security threats Turkey faces.

Rights groups and some of Turkey’s Western allies fear Erdogan is using the crackdown to stifle dissent and crush his opponents. Freedom House, a Washington-based watchdog, downgraded Turkey to “not free” from “partly free” in an annual report last month.

Turkey launched its Afrin operation, dubbed “Operation Olive Branch”, nearly two weeks ago to target Kurdish YPG fighters near its southern border. Turkey sees the militia as a terrorist group and an extension of the outlawed Kurdistan Workers Party (PKK).

Separately, authorities on Thursday ordered the detention of another 13 people in three provinces for protesting against the offensive, police said.

Additional reporting by Tulay Karadeniz and Gulsen Solaker; Editing by David Dolan, Larry King